Apparatus for trimming the edges of hollow bodies



' R. WIDA'NI A ril 1, 1969 v APPARATUS FOR TRIMMING THE EDGES OF HOLLOW BODIES Filed March 1 5, 1966 Sheet I'll l... 1|

BY Rum MA CVTORNBYS April 1, 1969 RMDAN. 3,435,718

APPARATUS FOR TRIMMING THE EDGES OF HOLLOW BODIES Filed arch 16, 1966 Sheet 2 or: r

XNVGNTOR United States Patent U.S. Cl. 83-185 4 Claims ABSTRACT OF THE DISCLOSURE There is shown a device for first trimming off in one piece a rough edge of a work piece such as a tubular member :and then splitting the trimmed-off edge into severalpieces to permit easy disposal thereof as scrap. To this end, the work piece is placed upon a cutting head securely mounted on a table. A first drive means moves an annular cutter surrounding the cutting edge of the head into and out of cutting engagement therewith to trim off in one piece the rough edge of the work piece. Thereupon, the trimmed off edge is split into two pieces by means of splitting knives or cutters which are driven by a second drive means independent of the first drive means. The timing of the splitting operation with reference to the trimming-off operation can be freely selected due to the provision of two independent drive means. The split trimmed-off pieces are disposed through openings in the table of the device.

The invention relates to a machine for cutting off or trimming a rough generally tubular edge of hollow bodies, in particular of pressed sheet metal parts, having a stationary cutting head serving as support for the workpiece and a cutting plate surrounding said cutting head, as well as a device for cutting up the sliced-off annular edge portion by means of splitting knives and for ejecting these cut-off parts.

An edge-trimming machine of such construction has been disclosed in Germant Patent 1,119,211. This machine has given good results.

In the aforementioned known machine, with regard to the splitting of the cut-off annular edge portion, the arrangement is such, that the splitting knives operate in dependence of the movement of the cutting plate. Thus, the annular portion cut off in a preceding working step is still in one piece at the onset of the next movement of the cutting plate which also moves the splitting knives into the cutting position. It may therefore happen that the next annular edge portion is cut off before the preceding one had been split and ejected. In such a case jammings may occur which are tiresome and time-consuming to remedy.

Consequently, the present invention is based on the task of creating, for an edge-trimming machine of the above described type, means for splitting the cut-ofi annular edge portion so that the same can be conveniently removed thus avoiding the danger of jamming.

This is achieved according to the present invention in a simple and progressive manner thereby, that the actuation of the splitting knives is effected separately from the movements of the cutting plate by means of a drive located underneath the machine table. Thus, the splitting knives are actuated according to a separate cycle, which is independent of the movements of the cutting plate. Generally, the embodiment will be one in which the movement of the splitting knives is initiated immediately upon termination of the cutting-plate movement or pos- "ice sibly before this. It is ensured hereby that the splitting and ejection of the cut-oflf annular edge portion are reliably terminated before the next cutting-ofl? step takes place.

The invention is advantageously carried into effect in the manner whereby the splitting knives, which co-operate with stationary counter-knives arranged underneath the cutting head, can be displaced to-and-fro by means of levers by means of a driven shaft. The latter can be hydraulically or pneumatically driven by means of a pressure cylinder.

In addition to those already mentioned, the invention offers the further advantage that the driving members for actuating the splitting knives may be arranged underneath the machine table, so that no structural components capable of impeding operations are located in the region of the cutting head and of the cutting plate above the machine table. This also makes possible a lateral ejection of the split trimmed-01f parts; it is effected advantageously normal to the axis of the cutting head movement on opposite sides transversely in relation to the longitudinal movement of the cutting plate.

Further advantages and features of the invention will be explained in the following description with reference to the accompanying drawings, which diagrammatically illustrates an exemplary embodiment of the invention and wherein:

FIG. 1 is a partial section through an edge-trimming machine with the drive of the sectioning knives, and

FIG. 2 is a plan view of FIG. 1.

A machine table 1 fixedly mounts a cutting head 2, upon which a hollow workpiece to be worked can be secured by means of a pressure plate (not shown) of the kind shown in the German patent. A cutting edge 3 of the cutting head 2 co-operates with a counter-edge 5 on a blade 7 of an insert plate 6, which is exchangeably mounted on a cutting plate 8 surrounding fixed cutting head 2. The cutting assembly 6, 7 and 8 may be held in position by a cover plate 21.

The plate 8 is driven by means of a cam disc 12, which rotates in an aperture 8a in the plate 8. The disc is provided with a radially projecting cam 12a, which in the initial position engages into a correspondingly formed recess 12b of the plate 8.

The drive of the cam disc does not need to be detailed here as it is conventional and does not concern the present invention. It is indicated by a drive shaft 20 mounting cam disc 12. The shaft should be visualized as being coupled to a suitable power drive means as shown for instance in my copending application Ser. No. 534,823 filed Mar. 16, 1966 and now issued as Patent No. 3,383,- 966.

It should be mentioned, however, that the cutting plate 8 is driven, advantageously, only with the aid of only one cam disc 12 arranged laterally on the work-table, so that the components of the drive of this cam disc are also accommodated laterally underneath the machine table.

The cutting plate 8 is pivotally mounted diametrically opposite to the cam disc 12 by means of a bearing pin 20 projecting into a slide block, said block being displaceable to-and-fro in a corresponding recess of the plate 8 in accordance with the longitudinal movement of the latter. This feature does not constitute part of the invention and hence need not to be discussed here in detail either. A suitable arrangement for pivoting plate 8 in reference to Table 1 parallel thereto is shown for instance in FIG. 1 of my aforesaid copending application.

Underneath the cutting head 2 there are located two fixed counter-knives or cutters 9, which co-operate with splitting knives 10, which are located diamet-rally opposite each other and are displaceable to-and-fro.

The annular edge portion of the workpiece is cut off by means of the cutting edges 3, 5 falls downwards into the space 11 where it is cut in two halves by the knives 9, 10. The two portions thus formed are then ejected in the direction of the arrows x and y (see FIG. 2).

The splitting knives are actuated by rocking levers or links 14 and 15 hinged to a shaft 13. Each lever 15 is hinged at 16 to a slidable block 22. Consequently, the knives 10, which are engaged by pushing levers 17, are moved from the rest position into the cutting position when the shaft 13 is moved from the position drawn in full lines in FIG. 1 into the position drawn in broken lines.

In the exemplary embodiment illustrated, the displacement of the shaft 13 is effected hydraulically or pneumatically by means of a pressure cylinder 18.

In addition to the advantages already explained, a machine constructed according to the invention offers the further advantage that the cutting stroke of the splitting knives 10 is adjustable according to requirements. It is thus not limited to the size of displacement of the cutting plate.

It is obvious that the pressure cylinder 18 is so operated that immediately after splitting the annular edge portion the return movement of the knives 10 into the initial position is initiated, so that the space 11 between the splitting knives is free to receive the next cut-off annular edge portion.

I claim:

1. A device for trimming off a rough edge of a hollow workpiece, comprising in combination:

a horizontally disposed table;

a cutting head having a peripheral horizontally disposed cutting edge fixedly mounted on said table, said head constituting a support for a workpiece to be trimmed;

a cutting plate slidably supported on said table parallel thereto and substantially coplanar with the cutting edge of the head and encompassing the same;

a first drive means coupled to said cutting plate for moving the same into and out of cutting engagement with the cutting edge of said head to effect trimming of]? in one piece the rough edge of a workpiece supported on said cutting head;

two pairs of splitting cutters disposed spaced apart between said table and the common plane of the cutting edge of the head and the cutting plate, one cutter of each pair being stationarily mounted and the other being movable into and out of cutting engagement with the respective stationary cutter;

a second drive means independent of the first drive means and disposed below said table; and

coupling means coupling said second drive means to the movable cutters of said pairs for moving said cutters into and out of cutting engagement with the stationary cutters to effect splitting of a trimmed-off edge portion into two pieces,

said table including an opening therethrough for disposal of split trimmed-off edge portions.

2. The device according to claim 1 wherein said coupling means comprise for each pair of cutters a linkage including an input link linked to the second drive means and an output link linked to the respective movable cutter, said output links extending through said table opening.

3. The device according to claim 1 wherein said pairs of cutters are disposed opposite of each other with reference to the peripheral outline of the cutting edge on the cutting head.

4. The device according to claim 1 wherein said second drive means is a reciprocating speed-variable drive means having an adjustable stroke.

References Cited UNITED STATES PATENTS 2,074,547 3/1937 Hessenbruch 83-923 X 2,702,597 2/1955 WickWire 83-923 X 2,742,086 4/1956 Reid 83-923 X JAMES M. MEISTER, Primary Examiner.

US. Cl. X.R. 

